Modern electronics and particularly telecommunication and computer technology require vast numbers of electrical contacts or connection systems comprising female and male contacts.
To ensure a maximum reliability for current passage between the female and male contacts, such contacts are provided with a coating of precious metal, usually gold or palladium or alloys thereof, at least in those areas of these components which come into engagement when contact is made. Frequently such metallic coatings are applied by electroplating the contacts.
For practical use it will be sufficient to electrodeposit precious metal only in those areas of female and male contacts which mate together when contact is established. The technology for plating select areas of components only is commonly called selective or functional plating.
The male parts of a connection system usually have the form of elongate objects, as square or round pins, blades, and the like. Existing technologies provide the capability to more or less accurately selectively electroplate precious metal onto such elongate components on all sides. However, in the majority of all connection systems, precious metal is only required on two opposite sides of a male contact which mate with the female contact.
In a complete connection system (that is, an assembly of several male and female contacts) in which gold is used as the contact coating material, the cost of the precious metal represents appr. 28% of the total connector system of which the largest part is required for coating the male parts of the system. As stated above, a large part of the gold presently applied to male connectors is plated in non-functional areas which are not used in the mating of the male contacts with their female counterparts.